extract another method

libtiledbsoma/src/soma/soma_array.cc

@@ -1178,14 +1178,13 @@ uint64_t SOMAArray::nnz_slow() {
 }
 
 std::vector<int64_t> SOMAArray::shape() {
-    // Two reasons for this:
+    // There are two reasons for this:
     // * Transitional, non-monolithic, phased, careful development for the
     //   new-shape feature
     // * Even after the new-shape feature is fully released, there will be old
     //   arrays on disk that were created before this feature existed.
     // So this is long-term code.
-    auto current_domain = tiledb::ArraySchemaExperimental::current_domain(
-        *ctx_->tiledb_ctx(), arr_->schema());
+    auto current_domain = _get_current_domain();
     if (current_domain.is_empty()) {
         return _tiledb_domain();
     } else {

libtiledbsoma/src/soma/soma_array.h

@@ -803,6 +803,18 @@ class SOMAArray : public SOMAObject {
 
     uint64_t _get_max_capacity(tiledb_datatype_t index_type);
 
+    /**
+     * The caller must check the return value for .is_empty() to see if this is
+     * a new-style array with current-domain support (.is_empty() is false) , or
+     * an old-style array without current-domain support (.is_empty() is true).
+     * We could implement this as a std::optional<CurrentDomain> return value
+     * here, but, that would be a redundant indicator.
+     */
+    CurrentDomain _get_current_domain() {
+        return tiledb::ArraySchemaExperimental::current_domain(
+            *ctx_->tiledb_ctx(), arr_->schema());
+    }
+
     /**
      * With old shape: core domain mapped to tiledbsoma shape; core current
      * domain did not exist.